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101.
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The article presents the platform “Pimp your landscape” (PYL), which aims firstly at the support of planners by simulating alternative land-use scenarios and by an evaluation of benefits or risks for regionally important ecosystem services. Second, PYL supports an integration of information on environmental and landscape conditions into impact assessment. Third, PYL supports the integration of impacts of planning measures on ecosystem services. PYL is a modified 2-D cellular automaton with GIS features. The cells have the major attribute “land-use type” and can be supplemented with additional information, such as specifics regarding geology, topography and climate. The GIS features support the delineation of non-cellular infrastructural elements, such as roads or water bodies. An evaluation matrix represents the core element of the system. In this matrix, values in a relative scale from 0 (lowest value) to 100 (highest value) are assigned to the land-use types and infrastructural elements depending on their effect on ecosystem services. The option to configure rules for describing the impact of environmental attributes and proximity effects on cell values and land-use transition probabilities is of particular importance. User interface and usage of the platform are demonstrated by an application case. Constraints and limits of the recent version are discussed, including the need to consider in the evaluation, landscape-structure aspects such as patch size, fragmentation and spatial connectivity. Regarding the further development, it is planned to include the impact of land management practices to support climate change adaptation and mitigation strategies in regional planning.  相似文献   
103.
Biological diversity--or biodiversity--is the term given to the variety of life on Earth and the natural patterns it forms. The biodiversity we see today is the fruit of billions of years of evolution, shaped by natural processes and, increasingly, by the influence of humans. It forms the web of life of which we are an integral part and upon which we so fully depend. The research on molecular biodiversity tries to lay the scientific foundation of a rational conservation policy that has its roots in various disciplines including systematics/taxonomy (species richness), present day ecology (diversity of ecological systems), and functional genetics (genetic diversity). The results of ongoing genome analyses (genome projects and expressed sequence tag projects) and the achievements of molecular evolution may allow us not only to quantitate the diversity of the present biota but also to extrapolate to their diversification in the future. A link between biodiversity and genomics/molecular evolution will create a platform which we hope may facilitate a sustainable management of organismic life and ensure its exploitation for human benefit. In the present review we outline possible strategies, using the Porifera (sponges) as a prominent example. On the basis of solid taxonomy and ecological data, the high value of this phylum for human application becomes obvious, especially with regard to the field of chemical ecology and the desire to find novel potential drugs for clinical use. In addition, the benefit of trying to make sense of molecular biodiversity using sponges as an example can be seen in the fact that the study of these animals, which are "living fossils", gives us a good insight into the history of our planet, especially with respect to the evolution of Metazoa.  相似文献   
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A hundred years of lectin research has led to the development of lectinology as an independent field of study. Although lectinology is in part related to immunology, fundamental differences exist. Lectins are important tools in biochemistry, histochemistry and clinical diagnosis. The essential in vivo function of lectins is to combine glycoconjugates. The function of lectins in microorganisms and in animals is partially known, whereas the function of lectins in plants is mostly unclear. Of special interest, now as before, are the toxic lectins of the ricin type consisting of an A-chain (N-glycosidase) and a B-chain (D-galactose-specific lectin).  相似文献   
106.
Summary The object of this study was to construct a measurement instrument to assess two different environmental world views of adolescents and, additionally, to address the adolescents' verbal commitment and actual behaviour. Using a multiple-choice questionnaire the instrument was designed to identify and measure the existing factors that underlie concern for ecological/environmental problems and behaviour towards environment/nature in the age group of 10 to 16 year old pupils. Within the traditional tripartite model covering cognitive, affective and behavioural components the study selected items that made up the majority of corresponding subscales from various previous studies. Using factor analysis the configuration of the scale's dimensionality was stated. Based on the responses of approximately 2000 Bavarian pupils, subscales were extracted via factor analysis and, subsequently, addressed to different segments of environmental concern ranging from attitudes to verbal commitment and actual behaviour. Correlation coefficients and the standardized Cronbach's -values were also surveyed. Additionally, a Kruskal-Wallis analysis was applied in order to locate the subscales' influences on sociodemographic variables such as gender and age and self-reported variables such as the pleasure of being a pupil and school performance. The further purpose of the present study is to provide the basis for follow-up comparisons of preferences and values in pupils within other countries.
Résumé Le but de la présente étude est la réalisation d'un système de mesure pour l'évaluation de différents niveaux de conscience par rapport à la nature et à la protection de l'environnement, ainsi que des comportements actuels ou envisagés. Le système de mesure s'appuie sur un questionnaire à choix multiples pour évaluer les différents facteurs qui déterminent les niveaux de conscience et les comportements correspondants chez les adolescents de 10 à 16 ans. Dans le cadre du modèle à trois niveaux, qui comprend des composantes cognitives, affectives et comportementales, un grand nombre d'items, en partie issus d'études antérieures, ont été sélectionnés pour former les sous-catégories nécessaires. La configuration des catégories a été garantie par une analyse factorielle.Sur la base des réponses d'environ 2000 élèves, des sous-catégories ont été définies, qui vont depuis les positions de départ jusqu'au comportement actuel. En outre, nous avons défini les coefficients de corrélation, ainsi que les valuers Cronback-Alpha, et une analyse des régressions a été effectuée, qui prend en compte les influences, par exemple, des variables sociodémographiques comme le sexe et l'âge, des résultats scolaires ou de la manière dont l'école est perçue par chacun.La présente étude représente la base aussi bien pour des investigations comparatives entre pays, que pour l'évaluation de l'influence d'un enseignement extra-scolaire adopté.


Dr. Franz Bogner is the senior author to whom correspondence should be addressed. Manfred Wilhelm is based at the Institut für Medizinische Statistik, Technische Universität, Ismaninger Straße 22, D-81675 München, Germany.  相似文献   
107.

The water balance for the site Mühleggerköpfl in the North Tyrolean Limestone Alps has been established to a soil depth of 50 cm. The evaporation amounts to 42% and deep percolation is 58 % of the precipitation. The surface runoff was negligible and therefore the according nitrate fluxes as well. Soil water analysis revealed mean nitrate concentrations of 3 to 15 mg NO3 L−1, depending on soil depth. The nitrate concentrations at 50 cm soil depth and the associated percolation rates led to NO2 N outputs of 15.9 kg NO3 N ha−1 in the year 1999 and 7.9 kg NO3 N ha−1 in the year 2000.

  相似文献   
108.
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Heterospecific matings are generally assumed to be unconditionally disadvantageous due to reduced viability or fertility of hybrid offspring. For female collared flycatchers (Ficedula albicollis) mated to male pied flycatchers (Ficedula hypoleuca), the cost of heterospecific pair formation is reduced due to high levels of conspecific extra-pair paternity and a male-biased offspring sex ratio. In order to investigate whether these cost-reducing mechanisms are the result of female mating strategies, rather than being a by-product of species incompatibilities, we manipulated the plumage of male collared flycatchers before pair formation to make them resemble male pied flycatchers. Since species incompatibilities are absent in this design, any systematic effect of manipulation on sex ratio or paternity would indicate a role of female mating strategy. Paternity was determined by means of a likelihood approach that controls the errors made in assigning a chick to be ‘within-pair’ or ‘extra-pair’. Neither the sex ratio nor the male share of paternity was affected by the manipulation in a systematic manner. We therefore conclude that our experimental data provide no support for the suggestion that female behavioural strategies are markedly adjusted in response to formation of mixed-species pairs. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
110.
Stief P  Hölker F 《Ecology》2006,87(12):3152-3159
Sediment-dwelling zoobenthos stimulate the mineralization of organic matter and alter nutrient cycling by aerating the sediment via burrows, by feeding on detritus, and by redistributing particles. Here we experimentally revealed that abundant benthic chironomids (Chironomus riparius) can perceive predatory fish (Rutilus rutilus) via chemical cues (kairomones) and spend less time foraging at the sediment surface and more time hiding in their burrows. This predator avoidance behavior significantly increased the exposure of freshly deposited organic particles to oxygen by reducing their burial to subsurface layers and by enhancing the aeration of subsurface layers via burrow ventilation, conditions that together increased the rate of organic matter mineralization. These results demonstrate that predatory fish can exert trait-mediated effects on benthic communities that in turn alter basic ecosystem processes related to nutrient cycling.  相似文献   
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